Here is the full list of all 29 Second Extinction achievements.
Kill 6666 Enemies.
Kill 2000 Enemies.
Deploy 100 times.
Play 20 missions at night.
Deploy 50 times.
Respawn 100 times.
Respawn 40 times.
Respawn 20 times.
Unlock all perks for one weapon.
Complete 40 Contracts.
Deploy 20 times.
Kill 750 Enemies.
Complete 20 Contracts.
Find the golden egg.
Deploy 10 times.
Complete the mission "Contact".
Complete all core missions.
Kill a T-Rex with a Supply Drop.
Complete the mission ”Black Site".
Complete 10 Contracts.
Complete the mission ”Research And Rescue".
Kill 20 Enemies with Supply Drops.
Complete the mission "Charged Extraction".
Complete the mission "Vestige".
Complete a mission without using a Health Stim.
Take a raptor with you when you extract.
Complete the mission "Homebound".
Complete a mission without any on the team having to respawn.
First Deployment.